<!--
 Copyright 2024 Google LLC

 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at

     http://www.apache.org/licenses/LICENSE-2.0

 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
-->

<template>
    <div class="card">
        <TreeTable
            :value="processTree"
            v-model:expandedKeys="expandedKeys"
            :filters="filters"
            filterMode="lenient"
            sortField="pid"
            :sortOrder="1"
            :rowHover="true"
        >
            <Column field="processname" header="Process" expander>
                <template #body="slotProps">
                    <span
                        :id="'process-' + slotProps.node.key"
                        class="cursor-pointer flex align-items-center"
                        @mouseenter="showTooltip($event, slotProps.node)"
                        @mouseleave="hideTooltip"
                    >
                        <span
                            class="text-lg text-overflow-ellipsis overflow-hidden white-space-nowrap inline-block max-w-20rem font-monospace"
                        >
                            {{ slotProps.node.data.processname }}
                        </span>
                        <span class="ml-2">- PID: {{ slotProps.node.data.pid }}</span>
                        <span v-if="slotProps.node.data.uniqueMatchCount > 0" class="font-italic ml-2 match-count">
                            ({{ slotProps.node.data.uniqueMatchCount }} unique
                            {{ slotProps.node.data.uniqueMatchCount > 1 ? "matches" : "match" }})
                        </span>
                    </span>
                </template>
            </Column>
            <Column field="pid" header="PID" sortable>
                <template #body="slotProps">
                    <span :style="{ color: getColorForId(slotProps.node.data.pid) }">
                        {{ slotProps.node.data.pid }}
                    </span>
                </template>
            </Column>
            <Column field="ppid" header="PPID" sortable>
                <template #body="slotProps">
                    <span :style="{ color: getColorForId(slotProps.node.data.ppid) }">
                        {{ slotProps.node.data.ppid }}
                    </span>
                </template>
            </Column>
        </TreeTable>

        <div
            v-if="tooltipVisible"
            class="fixed bg-gray-800 text-white p-3 border-round-sm z-5 max-w-50rem shadow-2"
            :style="tooltipStyle"
        >
            <div v-for="rule in currentNode.data.uniqueRules" :key="rule.name">
                • {{ rule.name }}
                <span class="font-italic match-count">
                    ({{ rule.matchCount }} {{ rule.scope }} {{ rule.matchCount > 1 ? "matches" : "match" }})
                </span>
                <LibraryTag v-if="rule.lib" />
            </div>
        </div>
    </div>
</template>

<script setup>
import { ref, computed, onMounted, onUnmounted } from "vue";
import TreeTable from "primevue/treetable";
import Column from "primevue/column";
import LibraryTag from "@/components/misc/LibraryTag.vue";

const props = defineProps({
    data: {
        type: Object,
        required: true
    },
    showLibraryRules: {
        type: Boolean,
        default: false
    }
});

const filters = ref({});
const expandedKeys = ref({});
const tooltipVisible = ref(false);
const currentNode = ref(null);
const tooltipStyle = ref({
    position: "fixed",
    top: "0px",
    left: "0px"
});

const getProcessIds = (location) => {
    if (!location || location.type === "no address") {
        return null;
    }
    if (Array.isArray(location.value) && location.value.length >= 2) {
        return {
            ppid: location.value[0],
            pid: location.value[1]
        };
    }
    return null;
};

const processTree = computed(() => {
    if (
        !props.data ||
        !props.data.meta ||
        !props.data.meta.analysis ||
        !props.data.meta.analysis.layout ||
        !props.data.meta.analysis.layout.processes
    ) {
        console.error("Invalid data structure");
        return [];
    }

    const processes = props.data.meta.analysis.layout.processes;
    const rules = props.data.rules || {};
    const processMap = new Map();

    // create all process nodes
    processes.forEach((process) => {
        if (!process.address || !Array.isArray(process.address.value) || process.address.value.length < 2) {
            console.warn("Invalid process structure", process);
            return;
        }
        const [ppid, pid] = process.address.value;
        processMap.set(pid, {
            key: `process-${pid}`,
            data: {
                processname: process.name || "<Unknown Process>",
                pid,
                ppid,
                uniqueMatchCount: 0,
                uniqueRules: new Map()
            },
            children: []
        });
    });

    // build the tree structure and add rule matches
    Object.entries(rules).forEach(([ruleName, rule]) => {
        if (!props.showLibraryRules && rule.meta && rule.meta.lib) return;
        if (!rule.matches || !Array.isArray(rule.matches)) return;

        rule.matches.forEach((match) => {
            if (!Array.isArray(match) || match.length === 0) return;
            const [location] = match;
            const ids = getProcessIds(location);
            if (ids && processMap.has(ids.pid)) {
                const processNode = processMap.get(ids.pid);
                if (!processNode.data.uniqueRules.has(ruleName)) {
                    processNode.data.uniqueMatchCount++;
                    processNode.data.uniqueRules.set(ruleName, {
                        name: ruleName,
                        lib: rule.meta && rule.meta.lib,
                        matchCount: 0,
                        scope: location.type
                    });
                }
                processNode.data.uniqueRules.get(ruleName).matchCount++;
            }
        });
    });
    // build the final tree structure
    const rootProcesses = [];
    processMap.forEach((processNode) => {
        processNode.data.uniqueRules = Array.from(processNode.data.uniqueRules.values());
        const parentProcess = processMap.get(processNode.data.ppid);
        if (parentProcess) {
            parentProcess.children.push(processNode);
        } else {
            rootProcesses.push(processNode);
        }
    });

    return rootProcesses;
});

const getColorForId = (id) => {
    if (id === undefined || id === null) return "black";
    const hue = Math.abs((id * 41) % 360);
    return `hsl(${hue}, 70%, 40%)`;
};

const showTooltip = (event, node) => {
    if (node.data.uniqueMatchCount > 0) {
        currentNode.value = node;
        tooltipVisible.value = true;
        updateTooltipPosition(event);
    }
};

const hideTooltip = () => {
    tooltipVisible.value = false;
    currentNode.value = null;
};

const updateTooltipPosition = (event) => {
    const offset = 10;
    tooltipStyle.value = {
        position: "fixed",
        top: `${event.clientY + offset}px`,
        left: `${event.clientX + offset}px`
    };
};

const handleMouseMove = (event) => {
    if (tooltipVisible.value) {
        updateTooltipPosition(event);
    }
};

onMounted(() => {
    document.addEventListener("mousemove", handleMouseMove);
});

onUnmounted(() => {
    document.removeEventListener("mousemove", handleMouseMove);
});
</script>
